Motion studies using sketches in a layout assembly;  I've been mucking with this all day and I'm ready to conclude that SW has not really invested the time to make sketches particularly usable for motion studies. Maybe that's why I seem to only see assembly-with-parts style motion studies (instead of Layout-Assembly-with-sketch-blocks). I'd like to do quick studies with blocks in 2D before investing the time to make parts, even simple parts.

For example, to rotate a block, you have to edit the sketch and do Tools/Sketch Tools/Rotate Entities.  I was expecting to see rotate handles to do it graphically. Also, Im finding that I can animate simple blocks (basically shows dragging to different keypoints), but more complicated blocks (one is nested, maybe it's getting confused on that) don't seem to work... I can see the "dragged" locations when I manually move the time line, but play doesn't make anything move.